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Finding the Fourth Proportional to 660.74, 991.55 and 455.49

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Solution

The fourth proportional to 660.74, 991.55 and 455.49 is: 683.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.74 : 991.55 = 455.49 : x
  2. Step 2: Convert to fraction form
    660.74/991.55 = 455.49/x
  3. Step 3: Cross multiply
    660.74x = 991.55 × 455.49
  4. Step 4: Simplify right side
    660.74x = 451,642.25
  5. Step 5: Solve for x
    x = 451,642.25/660.74
  6. Step 6: Final answer
    x = 683.55

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.